Always Bloated? SIBO Is the Digestive Disorder You Need to Know About

Bloating, gas, abdominal pain, and diarrhea or constipation? If this sounds like you, your gut bugs could be to blame.

Gut health has been linked to everything from chronic fatigue syndrome to breast cancer risk, and probiotics have become more popular as a result. While good bacteria are important, if they get into the wrong place, like your small intestine, they can wreak havoc on your stomach. So if your abs seem to be disappearing under a gassy belly despite your hard work in the gym, tune in.

Small intestine bacterial overgrowth (SIBO) happens when the bacteria of the colon are living in high numbers in the small bowel, explains gastroenterologist Mark Pimentel, M.D., executive director of the Medically Associated Science and Technology program at Cedars-Sinai in Los Angeles. When you ingest food, instead of getting all of the nutrients, the bacteria actually steals some. The the bacteria multiply, leading to gas and other symptoms, he says.

The tricky thing is that many doctors don't spot SIBO right away and instead diagnose you with IBS. Technically, they're not incorrect, but research has confirmed that 60 percent of IBS sufferers have SIBO. IBS sufferers make up about 10 percent of the total population, so we're talking about a LOT of people for such a little-discussed condition.

Here's how to tackle it.

Signs You May Have SIBO

Bloating and belly distention (some patients feel and look six months pregnant!), abdominal pain, cramping, and a change in bathroom habits are major indicators of bacterial overgrowth says Kate Scarlata, R.D.N. Other symptoms include nausea, fatigue, malnutrition, and weight loss.

You might feel like your pants are tighter than usual or you even have to loosen them after eating. That's gas building up from the bacteria fermenting, says Dr. Pimentel. And while it's normal to have some bloating around your period, if you have bacterial overgrowth, the bloating doesn't come and go with your cycle, he says.

Talk to a GI doc if you have these symptoms. They may order a breath test, which can determine if there are high levels of hydrogen or methane gases in your system. Some doctors may also prescribe an antibiotic to kill off the bacteria without first giving you the breath test. "If you take the antibiotic and are feeling 90 percent better, great—you had it," and the medicine is working, says Dr. Pimentel.

How to Get Rid of SIBO Initially

"SIBO requires a multifaceted approach including diet, antibiotics, stress management, and often more," says Scarlata. The first step is usually to start with a course of antibiotics. Rifaximin is an antibiotic clinically proven for IBS that actually stays within the gut.

"Our recent research has shown that people do not develop a resistance to this antibiotic the way they might to others," explains Dr. Pimentel. That's great news for people with the bacterial overgrowth, because depending on the severity of your case, you may have to take the drug anywhere from every few years to every few weeks. "If it works the first time, it almost always works again and again," he says.

How to Prevent a Relapse

Here's where it gets tricky. Rates of recurrence for bacterial overgrowth are high because it's likely caused by a slow-moving gut. So how did your gut turn slo-mo? A massive study from the Mayo Clinic published this year found that the onset of IBS can be pinned down to an incidence of food poisoning.

"So the timeline is, you ate some bad food, you got sick for 24 to 48 hours, and because of that, the nerves of your gut have been damaged. Now you've got this slow-moving gut and the bacteria starts to build up because of that," explains Dr. Pimentel.

You're stuck with the gut damage, but diet can help to relieve symptoms and hinder bacterial growth. The low FODMAP diet has been shown to help people with IBS, and since more than half of people with IBS have SIBO, it is one viable option, explains Scarlata. (Here's what it's really like to be on the low FODMAP diet.)

FODMAPs are specific small carbohydrates that are quickly and easily digested by your gut bacteria and can exacerbate their growth. By eating lower amounts of them, you can starve the bacteria. After eliminating them for a while, you systematically add them back in to determine if any trigger your symptoms.

The low fermentation diet, created by doctors atCedars-Sinai, is a less-intense version of the low FODMAP diet that eliminates some of the most highly fermentable foods. While this diet approach can be easier to follow, Scarlata advises against onions, garlic, and foods with excess fructose such as apples and pears, which are technically allowed on the low fermentation diet. "Those are trigger foods for many of my patients," she says. Meanwhile, butter, which is not allowed on the low fermentation diet, is usually fine.

Aside from the types of food you eat, spacing meals three to four hours apart (instead of grazing) can also help.

"I do not recommend following either of these diets long-term," warns Scarlata. "That being said, some patients will find their intolerance to some foods may be chronic. Working with a dietitian well versed in SIBO and GI nutrition can help the patient identify the best individualized diet for long-term well-being and gut health," she says.